title: Dosimetry of N⁶-formyllysine adducts following [¹³C²H₂]-formaldehyde exposures in rats.
abstract: With formaldehyde as the major source of endogenous N⁶-formyllysine protein adducts, we quantified endogenous and exogenous N⁶-formyllysine in the nasal epithelium of rats exposed by inhalation to 0.7, 2, 5.8, and 9.1 ppm [¹³C²H₂]-formaldehyde using liquid chromatography-coupled tandem mass spectrometry. Exogenous N⁶-formyllysine was detected in the nasal epithelium, with concentration-dependent formation in total as well as fractionated (cytoplasmic, membrane, nuclear) proteins, but was not detected in the lung, liver, or bone marrow. Endogenous adducts dominated at all exposure conditions, with a 6 h 9.1 ppm formaldehyde exposure resulting in one-third of the total load of N⁶-formyllysine being derived from exogenous sources. The results parallel previous studies of formaldehyde-induced DNA adducts.
authors.affiliation: Department of Biological Engineering, ‡Center for Environmental Health Sciences, Massachusetts Institute of Technology , Cambridge, Massachusetts, 02139, United States.
authors.forename: Bahar
authors.initials: B
authors.lastname: Edrissi
authors.forename: Koli
authors.initials: K
authors.lastname: Taghizadeh
authors.forename: Benjamin C
authors.initials: BC
authors.lastname: Moeller
authors.forename: Dean
authors.initials: D
authors.lastname: Kracko
authors.forename: Melanie
authors.initials: M
authors.lastname: Doyle-Eisele
authors.forename: James A
authors.initials: JA
authors.lastname: Swenberg
authors.forename: Peter C
authors.initials: PC
authors.lastname: Dedon
mesh_terms: D000818:Animals; D002247:Carbon Isotopes / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D005557:Formaldehyde / Q000737:chemistry* / Q000633:toxicity; D019570:Inhalation Exposure; D008239:Lysine / Q000032:analysis* / Q000737:chemistry; D008297:Male; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism; D009297:Nasal Mucosa / Q000187:drug effects / Q000378:metabolism; D011874:Radiometry; D051381:Rats; D053719:Tandem Mass Spectrometry; D013997:Time Factors
chemical_list: D002247:Carbon Isotopes; D008565:Membrane Proteins; D005557:Formaldehyde; D008239:Lysine